1. Field of the Invention
The present invention is related to an automotive engine control apparatus. More specifically, the present invention is directed to an automotive engine control apparatus capable of controlling both injection coils for driving of fuel-injecting electromagnetic valves and ignition coils with respect to injected fuel, while the fuel-injecting electromagnetic valves are provided in correspondence with the respective cylinders of an automotive multi-cylinder engine.
2. Description of the Related Art
Conventionally, as to electromagnetic coils such as injection coils capable of driving fuel-injecting electromagnetic valves and ignition coils capable of igniting injected fuel, both voltages and currents appeared in the respective circuit portions of coil drive circuits are monitored to detect disconnection/shortcircuit malfunction with respect to electromagnetic coils, wiring lines, and switch elements and the like. Furthermore, such a method of detecting a malfunction is known in this field, by which malfunction detection signals with respect to loads in multi-channels are OR-gated with each other to simplify signal processing operation.
Japanese Patent Laid-open No. 10-257799 discloses xe2x80x9cAN OUTPUT-OPEN DETECTING APPARATUS OF A MULTI-CHANNEL OUTPUT APPARATUS.xe2x80x9d This output-open detecting apparatus detects disconnections by utilizing such a fact that while a very small current is supplied to a multi-channel load, for example, an energizing coil of a stepping motor when the multi-channel load is not driven, if a disconnection occurs in this multi-channel load circuit, voltages at the opposing ends of the load are increased. Although this output-open detecting apparatus does not disclose detections of shortcircuited loads, this detecting apparatus discloses a method in which the disconnection detection signals are OR-gated by the diode OR-gate circuit, and the OR-gated signal is supplied to the commonly-used comparing/judging circuit.
In contrast, Japanese Patent Publication No. 7-92016 discloses xe2x80x9cA MALFUNCTION DETECTION CIRCUIT OF A FUEL INJECTING VALVE DRIVING CIRCUIT FOR INTERNAL COMBUSTION ENGINE.xe2x80x9d This malfunction detection circuit detects a surge voltage which is generated when a supply of a current to a fuel-injecting-valve driving electromagnetic coil is interrupted, so that this malfunction detection circuit can detect disconnection/shortcircuit malfunction of electromagnetic coils/wiring lines/switch elements and the like in a batch manner.
Also, Japanese Patent Laid-open No. 9-112735 discloses xe2x80x9cAN ELECTROMAGNETIC VALVE DRIVING APPARATUS.xe2x80x9d In a method according to this invention, for example, as to a driving electromagnetic coil for a fuel-injecting electromagnetic valve, both a quick-driving voltage boosting circuit and an operation holding low current circuit are employed. Further, the disconnections and shortcircuits of the plural electromagnetic coils and also the wiring lines thereof are detected by monitoring the charging voltage and the discharging voltage of the capacitor employed in the voltage boosting circuit. In particular, in this prior art, there is shown a method in which a plurality of fuel-injecting-valve driving electromagnetic coils are grouped, and thus the turn-out drive operation can be carried out in a smooth manner based upon the malfunction judgment result.
Further, Japanese Patent Laid-open No. 10-318025 discloses xe2x80x9cA CONTROL APPARATUS FOR A FUEL-INJECTING INJECTOR.xe2x80x9d In this control apparatus, a plurality of injector coils are controlled to be turned ON/OFF, while one ends of these injector coils are connected to the commonly-used drive output circuit, and the other ends of these injector coils are connected to the separate switching means which are turned ON/OFF at the energizing timing for the respective injector coils. These plural injector coils are designed such that the fuel injection sequences thereof are separated from each other by approximately two strokes or more, and furthermore, the energizing timing thereof is not overlapped with each other.
On the other hand, xe2x80x9cA COMBUSTION CONDITION DETECTING APPARATUS OF INTERNAL COMBUSTION ENGINExe2x80x9d of Japanese Patent Laid-open No. 2001-65445 discloses such a conceptional idea that an ignition ion current generated in a cylinder is detected to judge whether or not an abnormal state occurs in an ignition system.
Furthermore, Japanese Patent Laid-open No. 7-109969 discloses xe2x80x9cAN IGNITION APPARATUS FOR MULTI-CYLINDER TYPE INTERNAL COMBUSTION ENGINE.xe2x80x9d According to an ignition apparatus of this invention, there is shown a method in which misfire detection circuits are provided on the respective primary coil sides of plural ignition coils and the operations of all of these ignition coils are stopped so as to stop the engine when an abnormal state occurs in some of these ignition coils.
Also, Japanese Patent Laid-open No. 12-380652 discloses xe2x80x9cAN ABNORMAL STATE DETECTING APPARATUS OF AN ON-VEHICLE ELECTRIC LOAD DRIVING SYSTEM.xe2x80x9d According to an abnormal state detecting apparatus of this invention, there is shown a method in which an abnormal state detection signal which has been OR-gated is detected in a separation manner within a microprocessor.
As previously described, the various types of conventional abnormal state detecting methods have been proposed with respect to the disconnections/shortcircuits of the electric loads such as various sorts of electromagnetic coils, and further, as to the disconnections/shortcircuits of the switch control elements used for these electromagnetic coils and wiring lines. However, these prior art systems do not constitute a means capable of mutually combining a fuel injection system with an ignition coil system, and thus capable of systematically judging whether or not an abnormal state occurs in both these systems. Instead, since the turn-out drive operation is carried out based upon the abnormal state judgment result as to any one of these fuel injection system and ignition coil system in these prior art systems, there are the following problems. That is, while the turn-out drive operation is performed, non-combustion gas may be exhausted, and electric energy may be uselessly consumed, so that the turn-out drive operation cannot be carried out under the stable condition.
The present invention has been made to solve the above-described problems, and an object of the present invention is threrfore to provide an automotive engine control apparatus capable of performing a turn-out drive operation under the stable condition based upon abnormal state judgment results of both a fuel injection system and an ignition coil system.
To achieve the above-described object, according to an aspect of the present invention, there is provided an automotive engine control apparatus for controlling an automotive engine equipped with injection coils capable of driving fuel injection electromagnetic valves with respect to the respective cylinders of a multi-cylinder engine, and ignition apparatus provided with the respective cylinders, for performing ignition operations with respect to injected fuel; comprising: control means for controlling an internal operation of the automotive engine control apparatus; a first switch element for sequentially driving the respective injection coils in response to a pulse series of an ignition drive signal generated by the control means; a first detection circuit for detecting that at least the injection coils are turned ON/OFF; first abnormal state judging means for comparing a detection signal derived from the first detection circuit with the injection drive signal to judge whether or not said injection coils are operated under normal state with respect to each of the cylinders; first abnormal state storage means for storing thereinto a judgment result obtained by the first abnormal state judging means with respect to each of the cylinders; a second switch element for sequentially driving the respective ignition apparatus in response to a pulse series of an ignition drive signal generated by the control means; a second detection circuit for detecting that at least the respective ignition apparatus are turned ON/OFF; second abnormal state judging means for comparing a detection signal derived from the second detection circuit with the ignition drive signal to judge whether or not the ignition apparatus is operated under the normal state with respect to each of the cylinders; second abnormal state storage means for storing thereinto a judgment result obtained by the second abnormal state judging means with respect to each of the cylinders; drive stopping means for stopping both the fuel injection operation and the ignition drive operation as to a cylinder operated under the abnormal state, which is stored into any one of the first and second abnormal state storage means; and storage prohibiting means operated in such a manner that when any one of the first and second abnormal state storage means stores thereinto the judgment result of the cylinder operated under the abnormal state, the other of the first and second abnormal state storage means is prohibited from storing thereinto the judgment result.
Also, according to another aspect of the present invention, there is provided an automotive engine control apparatus for controlling an automotive engine equipped with injection coils capable of driving fuel injection electromagnetic valves with respect to the respective cylinders of a multi-cylinder engine, and ignition apparatus provided with the respective cylinders, for performing ignition operations with respect to injected fuel, in which: each of the cylinders composes a cylinder group in conjunction with another cylinder thereof, the injection timing of which is separated by even-numbered timing from the injection timing of the first-mentioned cylinder; and the automotive engine control apparatus is comprised of: control means for controlling an internal operation of the automotive engine control apparatus; a first switch element for sequentially driving the respective injection coils in response to a pulse series of an ignition drive signal generated by the control means; a first detection circuit for detecting that at least the injection coils are turned ON/OFF; first abnormal state judging means for comparing a detection signal derived from the first detection circuit with the injection drive signal to judge whether or not said injection coils are operated under the normal state with respect to each of the cylinders; first abnormal state storage means for storing thereinto a judgment result obtained by the first abnormal state judging means with respect to each of the cylinders; a second switch element for sequentially driving the respective ignition apparatus in response to a pulse series of an ignition drive signal generated by the control means; a second detection circuit for detecting that at least the respective ignition apparatus are turned ON/OFF; second abnormal state judging means for comparing a detection signal derived from the second detection circuit with the ignition drive signal judge whether or not the ignition apparatus is operated under the normal state with respect to each of the cylinders; second abnormal state storage means for storing thereinto a judgment result obtained by the second abnormal state judging means with respect to each of the cylinders; and cylinder group drive stopping means for stopping both fuel injection operations and ignition drive operations related to a cylinder operated under the abnormal state which is stored into any one of the first and second abnormal state storage means, and also related to all of other cylinders which compose a cylinder group in conjunction with the cylinder operated under the abnormal state.
Also, the automotive engine control apparatus further comprises recovery means for causing both the fuel injection operation and the ignition drive operation to become active with respect to a cylinder whose information is not stored in the first and second abnormal state storage means in the case where the drive operations of plural cylinder groups are stopped by the cylinder group drive stopping means.
Also, the automotive engine control apparatus further comprises: interconnection storage prohibiting means which prohibits, in the case where any one of the first and second abnormal state storage means stores thereinto the judgment result of the cylinder operated under the abnormal state, such operations that the other of the first and second abnormal state storage means stores thereinto the judgment result, and also prohibits judgment results related to all of other cylinders which compose a cylinder group in conjunction with the cylinder operated under the abnormal state from being stored into both the first and second abnormal state storage means.
Also, the first detection circuit is an off-surge voltage detection circuit used for the first switch element provided with respect to the injection coils; and the detection signal is supplied to the control means via an OR-gate circuit employed between the off-surge voltage detection circuit and the control means.
Also, the ignition apparatus includes an ignition primary coil; the second detection circuit is an off-surge voltage detection circuit for detecting a current interrupt of the ignition primary coil; and the detection signal is supplied to the control means via an OR-gate circuit provided between the off-surge voltage detection circuit and the control means.
Also, the ignition apparatus includes an ignition secondary coil; the second detection circuit is a discharge current detection circuit for detecting a discharge current of the ignition secondary coil; and the detection signal is supplied to the control means via an OR-gate circuit provided between the off-surge voltage detection circuit and the control means.
Also, the automotive engine control apparatus further comprises a warning/display apparatus for notifying the abnormal state in the case where any one of the first abnormal state storage means and the second abnormal state storage means stores thereinto the judgment result of the cylinder operated under the abnormal state.
Also, the automotive engine control apparatus further comprises warning/display synthesizing means for issuing such a notification that the abnormal state occurred in an injection system/ignition system/cylinder system is not discriminated from each other in the case where any one of the first and second abnormal state storage means stores thereinto the judgment result of the cylinder operated under the abnormal state; and the warning/display apparatus is operated in response to a signal supplied from the warning/display synthesizing means.
Also, the automotive engine control apparatus further comprises a communication interface circuit for communicating with a predetermined external tool provided outside of the automotive engine control apparatus; display/transmission means for transmitting/displaying malfunction information to/on the external tool; and reset means for initializing the storage contents of the first and second abnormal state storage means by means of the external tool.